Image capture method, device and system

ABSTRACT

A captured image of a scene is modified by detecting an inhibit signal emanating from an inhibitor device carried by an object within the scene. In response to receipt of the inhibit signal, identifying a portion of the image corresponding to the object. The image object of the scene is modified by obscuring the image portion of the object.

FIELD OF THE INVENTION

[0001] The present invention relates to the field of image capture.

BACKGROUND TO THE INVENTION

[0002] Portable digital cameras have become miniaturized, and arebecoming increasingly wide spread. Known mobile phone devices alreadyhave built in cameras, and picture messaging between mobile phones is anincreasingly wide spread technology.

[0003] Further, wearable cameras are known, and have the potential forbecoming widely used consumer products in the future.

[0004] For some persons, being included in photographs or picturemessages when in public places has nuisance effect. Increasing usage ofportable camera devices means that the privacy issue of capturing ofimages of subjects who would prefer not to be photographed hasincreased. Because portable cameras are small and are likely to beunseen by a subject, persons generally cannot choose to avoid being inthe field of view of a small portable camera and are likely to havetheir pictures taken without their knowledge or consent.

[0005] The issue of privacy in relation to cameras is well known. Civilliberties organizations campaign for the right for people not to bephotographed or videoed without their consent. However, with thewidespread use of security cameras and other hand held portable cameradevices, maintaining privacy from being photographed or videoed isbecoming more difficult. Some security companies market their productsas ‘privacy friendly’ because they are supposed to retain only imagescontaining faces of known individuals, typically, potential or actualcriminals. In ‘Privacy issues of wearable camera's—v—surveillancecameras’ by Steve Mann—HTTP//wearcam.org, 1995, it is suggested thatsecurity camera or wearable cameras should be made visible, and that awearable camera should have a visual indicator that it is active forcapturing an image. This does not offer actual privacy to individualswithin the vicinity of the camera, but rather offers a chance to‘escape’ from the field of view from a camera.

[0006] JP 10031265 discloses a device for preventing stealthyphotographing in which a remote control receiver remotely controls acamera. The remote control receiver issues a warning sound when a cameracaptures an image. This does not prevent capture of a person's image,but rather alerts a person that a picture has been or could be taken.

[0007] Further, there are known security systems which are able todetect and identify faces of known criminals from security videofootage, such as those available from Identix, and Viisage, for examplethe known FaceFINDER product.

[0008] US 20020039447 discloses a system for indexing, storage andretrieval of digital images, whereby photographs are sorted according towho is in a photograph, through face recognition algorithms.

[0009] US 20010016820 discloses a face identification system, wherebyfaces are removed from a memory device, having been identified.

[0010] JP 2001235812 discloses an image processing method and apparatushaving a digital processing device with a masking pattern which can besuperimposed on a portion of an image for obscuring that portion of theimage. Control of the masking process lies with the operator of thephotographic processing device. A person whose image has been capturedby the device has no control over the processing of the image or whetherthe image can be captured or not.

[0011] The Imageld company www.imagelD.com has a known product, wherebya user wears a tag. The tags are recognized by cameras and used to sortout images of people. The product recognizes and reads a set of markingswithin an image, and then sorts and stores matching identification codesin a database.

[0012] U.S. Pat. No. 6,067,399 discloses a privacy mode for cameras andcamcorders. Images of persons' faces recorded on a camera or camcorderare detected and obscured. In U.S. Pat. No. 6,067,399 the person whoseimage is being captured has no control over whether a privacy mode of acamera or camcorder apparatus is set or not. Instead, an operator of thecamera/camcorder determines the privacy mode. Therefore, privacy is notin the control of a person whose image is being captured.

[0013] JP 2001313006, discloses a method and apparatus in which a personwho does not wish to be photographed carried a portable device whichemits infra-red light which ‘floods’ a sensor or film of a camera,thereby blanking the image. However, the method disclosed in JP2001313006 disables image capture completely and inhibits all imagesbeing taken, within range of the device.

SUMMARY OF THE INVENTION

[0014] According to one aspect a captured image of a scene is modifiedby a method and apparatus for detecting an inhibit signal emanating froman inhibitor device carried by a person within the scene. In response tothe inhibit signal, (a) a portion of the image corresponding to theperson is identified; and (b) the image of the scene is modified toobscure the image portion of the person.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] For a better understanding of the invention and to show how thesame can be carried into effect, there is now described by way ofexample only, specific embodiments, methods and processes according tothe present invention with reference to the accompanying drawings inwhich:

[0016]FIG. 1 is a schematic illustration of a first embodiment of animage capture system comprising an image capture device, and at leastone inhibitor device for controlling operation of the image capturedevice for taking images of a host wearer of the inhibitor device;

[0017]FIG. 2 is a schematic illustration of an omni-directionalcommunication link between an inhibitor device and an image capturedevice of the system of FIG. 1;

[0018]FIG. 3 is a schematic illustration of a second embodiment imagecapture system, in which a communication link uses a directionalreceiver beam between an image capture device and an inhibitor device inwhich the image capture device detects the inhibitor device;

[0019]FIG. 4 is a schematic illustration of the inhibitor device andcamera device of FIG. 3, in which the image capture device points in adirection away from the inhibitor device;

[0020]FIG. 5 is a schematic illustration of a scenario of two inhibitordevices and a single image capture device, the inhibitor device being ina field of view of the image capture device;

[0021]FIG. 6 is a schematic illustration of an example of an imagecaptured by an image capture device before image processing is applied;

[0022]FIG. 7 is a schematic illustration of the image of FIG. 6, afterimage processing is applied to modify the image taking account ofinhibitor devices within a field of view of the image capture device;

[0023]FIG. 8 is a schematic illustration of components of one specificembodiment of an inhibitor device;

[0024]FIG. 9 is a schematic illustration of components of a specificembodiment of an image capture device;

[0025]FIG. 10 is a schematic illustration of a scenario in which animage capture device captures an image in a field of view which includesusers wearing first and second inhibitor devices, and the image capturedevice recognizes one of the inhibitor devices;

[0026]FIG. 11 is a schematic illustration of processes carried out by animage capture device for recognizing an inhibitor device;

[0027]FIG. 12 is a schematic illustration of a signal processing channelwithin an image capture device;

[0028]FIG. 13 is a schematic illustration of a communication linkbetween an image capture device and a remote third party, for obtainingauthorization for decoding a portion of a captured image; and

[0029]FIG. 14 is a schematic illustration of an image captured device,an inhibitor and a trusted third party.

DETAILED DESCRIPTION OF THE DRAWING

[0030] There is now described by way of example only specificembodiments of the invention. In the following description numerousspecific details are set forth in order to provide a thoroughunderstanding. It will be apparent however, to one of ordinary skill inthe art, that the present invention can be practiced without limitationto these specific details. In other instances, well known methods andstructures have not been described in detail so as not to unnecessarilyobscure the description.

[0031] In this document, the term ‘scene image’, relates to anelectronic image of a scene, and includes both a still image, and avideo sequence.

[0032] In this document, the term ‘image capture device’ relates to anydevice capable of capturing an image, and includes but is not limited todigital still cameras, and video cameras.

[0033] Specific embodiments relate to a person's image being madeavailable to an image capture device, particularly although notexclusively a portable image capture device, without the consent of theperson.

[0034] In one embodiment, a wearable device broadcasts an inhibitmessage to an area immediately surrounding a host wearer of the device.Any portable image capture devices, such as cameras or the like of thirdparties within range of the device receive the inhibit message, and inresponse to receiving the inhibit message, inhibit capture and/or applyprocessing of an image or part of an image.

[0035] Referring to FIG. 1 herein, there is illustrated schematically aninhibitor device 100 and an image capture device 101 in close proximity,in which the inhibitor device broadcasts an inhibit signal carrying animage capture inhibitor message. Camera device 101, picks up the signalcarrying the inhibit message. On receiving the inhibit message, theimage capture device reacts in various ways.

[0036] In one mode of operation, the image capture device 101 capturesan image of a scene, which includes a host wearer of the inhibitordevice 100. However, the image capture device 101 is unable to print orstore a portion of the captured scene image which corresponds to awearer of the inhibitor device 100. Data processing components withinthe image capture device 101 modify the scene image by (1) identifyingareas of the scene image which relate to a person wearing inhibitordevice 100, and (2) obliterating selected parts of the image of thewearer of the inhibitor device. The selected parts of the image whichare obliterated typically comprise facial features, and also can includeitems of clothing.

[0037] Some specific embodiments described herein operate such thatimages which include people who prefer not to have their images capturedare automatically and forcefully modified before viewing. In someembodiments the images are modified before storage, such that images ofsuch persons are no longer recognizable in the captured image. Suitably,only the portion of an overall image which relates to a person who seeksprivacy is obliterated from the image, leaving the remainder of theoverall image intact.

[0038] The inhibitor device 100 sends an inhibit message eitheromni-directionally, or directionally. The image capture device 101 canreceive one or more inhibit messages at the same time, eitheromni-directionally, or directionally.

[0039] The inhibit message sent by device 100 can be carried on a signalcarrier including but not limited to an ultrasonic signal carrier; amicrowave signal carrier; a radio frequency signal carrier; a visuallight signal, or an infrared light signal.

[0040] In the second mode of operation an inhibit signal generated froma position within a field of view of image capture device 101 isidentified, and its position within a capture image taken of that fieldof view is established. Having established the position of the inhibitsignal within the field of view and its position within a capturedimage, a portion of the image relating to a wearer of the inhibitordevice is located. This can be done by device 101 using a patternrecognition algorithm. A suitable face detection algorithm is disclosedin ‘Neural network based face detection’ Rowley, Baluga, Kanade, IEEEPAMI 20(1): pages 23-38. Capture device 101 identifies an image of ahost wearer's face, device 101 can employ a further image-processingalgorithm to obliterate or obscure details of the person's face. Thiscan be done by reducing the resolution of the image corresponding to theperson's face, or by blanking out that portion of the image, or anyother like obliteration or obscuring method of the portion of the image.

[0041] In one specific embodiment, the inhibit message from device 100is carried by an inhibit signal in the form of a physical light, or aninfrared light. Such a light is detected by device 101 within thecaptured image, as a high intensity light spot. Device 101 therebyidentifies within the image, the position of a wearer of the inhibitordevice 101. In this embodiment, there is a line of sight view betweenthe inhibitor device 100, and the image capture device 101.

[0042] In other embodiments, the inhibitor device 100 sends anultrasonic signal, or a radio frequency signal or a microwave signal, inwhich case a line of sight between the image capture device 101 and theinhibitor device 100 is not essential, but the image capture deviceincludes a receiver device to detect the energy emitted by the inhibitordevice. The problem of device 101 locating the position of the inhibitordevice 100 within a captured image needs to be addressed.

[0043]FIG. 2 includes an omni-directional pattern having circular −3 dBlevel 200 associated with a signal transmitted by an inhibitor device201. There is also shown an image capture device 202 having a receiverhaving an omni-directional pattern with a circular −3 dB level 203.Since the inhibitor device 201 transmits omni-directionally and theimage capture device 202 receives an inhibit message with anomni-directional receive pattern, whenever the inhibitor device 201 iswithin close enough range of the image capture device to receive theinhibit message, the image capture device 202 is inhibited.

[0044] However, in other embodiments, the image capture device and/orthe inhibitor device have directional responses for sending and/orreceiving an inhibit message.

[0045] Referring to FIG. 3 herein, there is illustrated schematically aninhibitor device 300 having an omni-directional pattern represented by acircular−3 dB power level 301, and an image capture device 302 having adirectional receive beam represented by an elongated −3 dB level 303.When the image capture device 301 is pointing in a direction toward theinhibitor device 300, and device 301 is within range of being able tocapture and recognize an inhibit message transmitted by the inhibitordevice, the image capture device 301 is inhibited according to the modesdescribed herein above.

[0046] In FIG. 4, the image capture device 302 and inhibitor device 300of FIG. 3 are positioned so narrow beam 303 of the image capture devicepoints away from the inhibitor device. Because the receive beam 303 ofthe image capture device 302 is directional, the image capture device isnot inhibited even though the image capture device and inhibitor devicemay be in relatively close proximity. This is because the image capturedevice 302 points away from the inhibitor device 300 and device 302 hasa narrow inhibitor receive beam that corresponds with the optical fieldof view of device 302.

[0047] In this embodiment, the directional beam 303 of the image capturedevice 302 correspond with an optical field of view of image capture ofdevice 302, such that when the image capture device is pointing in aparticular direction for capturing an optical image of a scene, theinhibit receive beam of the image capture device coincides with theoptical field of view. Signals from inhibitor devices 300 which areoutside the optical field of view of the image capture device 302 arenot acted upon by the image capture device, so that the image capturedevice is not inhibited by inhibitor devices 300 outside the opticalfield of view of device 302.

[0048]FIG. 5 is a schematic illustration of first and second inhibitordevices, 500, 501 respectively, worn by first and second persons (notshown) facing opposite to each other. Image capture device 502 is heldor worn by a third person who is in the vicinity of the first and secondpersons wearing devices 500 and 501.

[0049] Each inhibitor device 500, 501 has a correspondingomni-directional antenna which produces a transmit pattern having acorresponding −3 dB level 503, 504 respectively. Image capture device502 has a receiver having a plurality of directional, relatively narrowinhibit receive beam patterns 505 to 509, pointing in differentdirections from each other and relative to a primary (front) lookdirection 510 of the optical image of image capture device. Beams 505and 509 have axes displaced by approximately 70° to the left and rightof direction 510, beams 506 and 508 have axes displaced by approximately45° to the left and right of direction 50, and central beam 507 has anaxis substantially aligned with direction 510.

[0050] The plurality of directional beams 505-509 enable the imagecapture device 502 to distinguish between the first and second inhibitordevices 500, 501 within a field of view of the image capture device,identified as being between straight line extremities 511, 512, that areequal angles relative to direction 510. The beam with inhibit pattern503 from first inhibitor device 500 is received on central beam 507 andfirst left beam 506 of the image capture device 502, whilst a secondinhibitor message on the beam with inhibit pattern 504 from secondinhibitor device 501 is received on the center beam 507 and first rightbeam 508.

[0051] However if an operator of the image capture device 502 swings theimage capture device so that the field of view points towards theinhibitor device 500, then the directional receive beam 506 of the imagecapture device 502 receives a signal from inhibitor device 500, and theimage capture device is inhibited according to the above describedinhibited modes.

[0052] Processing steps carried out by an image capture device in asecond mode of operation are described with reference to FIGS. 6 and 7.

[0053]FIG. 6 is a captured still image of a scene in which a primarysubject of the image is a violinist. However, because the image iscaptured in a public place, a restaurant in this case, the background ofthe scene image includes images of two other persons.

[0054] A person capturing the image using an image capture device islikely to have no interest in the two diners in the background. However,in the absence of any mechanism for protection against capture of theirimages the two diners have no choice but to be included in the imagescene. The person capturing the image can use the image for his ownpurposes, including putting the image publicly in the Internet, orotherwise publishing the image. This is likely to occur without theknowledge of the two persons whose images are in the background of thescene image. The persons included in the background of the image mightobject to being included in the image, if they had known the image hadbeen captured.

[0055]FIG. 7 includes the same image scene as FIG. 6, but after dataprocessing by an image capture device as described herein. The image ofFIG. 7 was obtained as a result of the two diners wearing inhibitdevices and the photographer using a capture device that has receivedinhibit messages from each of the diners in the background of the imagescene.

[0056] The image capture device receives two inhibit messages, one fromeach inhibitor device, worn by each of the diners. In response to eachinhibit message, the image capture device identifies a person wearingthe corresponding inhibitor device. The image capture device processeseach frame of image data, to identify images of individual wearers ofthe inhibitor devices, and then applies data processing to obliterate orremove portions of the image relating to the individual wearers of theinhibitor devices.

[0057] Correlation of an inhibit signal to a person in an image can bedone in several ways. According to one embodiment, using knownface-recognition software (for example as mentioned supra), the facenearest to the perceived origin of the inhibitor signal is located in areference frame defined by the image, and the located face mosaiced outof the image by processing circuitry included in the image capturedevice.

[0058] As shown in FIG. 7, this results in a blurring of the face ofeach of the diners in the resultant image frame, thereby protecting theidentity and privacy of each of those persons.

[0059] A portion of the image scene corresponding to a person's face orother features of the person is inhibited by obscuring, restrictingusage of, replacing and/or deleting the part of the image by variousmethods including, but not limited to the following:

[0060] Firstly, the image detector can decrease resolution of the facialimage portion, so that facial features become blurred and difficult fora human eye to resolve with accuracy. The decreased resolution can beachieved by a digital filtering algorithm, which applies a decrease inresolution to the image portion corresponding to a facial feature of aperson.

[0061] The image detector can alternatively identify a portion of theimage by a known algorithm for detecting skin tone colours within theimage scene. The portion of the image corresponding to a person's faceis obscured by overlaying a pre-determined graphic on that portion ofthe image, to obscure or obliterate facial features or other bodyfeatures of the person.

[0062] The image detector can alternatively de-focus a portion of theimage scene corresponding to a person's face or other body features sothat it is difficult visually for a viewer to resolve the image with anydetail.

[0063] Another approach is for the image detector to obscure the imageportion corresponding to the person's face or other body features bychanging an intensity level of the image portion. Typically, the imageportion is darkened to obscure facial features.

[0064] The image detector can also completely delete the facial or otherbody portion of the image and replace it with a different image, such asa duplicate of another adjacent portion of the image scene. For example,in the images shown in FIGS. 6 and 7, a portion of the image scenecorresponding to a person's face can be identified and removed from theimage scene. The resulting gap in the image is replaced by an adjacentportion of the image scene, for example a background wall. The imagedetector overlays a wall on the gap of the image produced by removal ofthe image portion corresponding to the person's facial features or otherbody features. This has the advantage of retaining similar colouring asadjacent portions of the image.

[0065]FIG. 8 is a block diagram of components of an inhibitor device800, corresponding to each of devices 100, 201, 300, 500 and 501. Theinhibitor device 800 comprises a casing 801 containing a battery (notshown), a size and shape such that the casing easily worn by a person,or can be easily carried by a person, for example in the person'spocket. Casing 800 includes: (1) an inhibit message generator 802 forgenerating one or a plurality of inhibit message types; (2) atransmitter device 803 for transmitting one or more inhibit messages ona carrier signal; (3) an antenna 804 for generating an omni-directionalinhibit transmit beam or one or a plurality of directional inhibittransmit beams; and a set of user controls 805 for enabling a person toturn the inhibitor device 80 on or off, and optionally for selecting aninhibit message type. Transmitter 803 is of any suitable type, e.g.; RF,microwave, optical or sonic. The battery powers each of generator 802,transmitter 803, and user controls 805.

[0066] The inhibitor device 800 can also comprise a memory devicecapable of storing a plurality of images of a person's face, in aplurality of views or orientations, and be capable of transmitting theimages either in encoded or in un-encoded format.

[0067]FIG. 9 is a block diagram of components of an image capture device900, corresponding to each of devices 101, 202, 302 or 502. The imagecapture device 100 comprises a casing 901 containing a battery or otherpower supply and an antenna 902 for receiving inhibit messages fromantenna 804. Antenna 902 has either an omni-directional receive beam, orone or plural directional receive beams. Device 900 also includesreceiver device 903 for receiving, amplifying and digitising a signalfrom antenna 902. Direction finder 904 responds to the signal fromreceiver 903 for identifying the direction from which an inhibit signalincludes on antenna 902 has been received, that is, for identifying fromwhich one or more of a set of directional beams, an inhibit signal wasreceived on. Direction finder 904 drives message recogniser 905 forextracting inhibit messages from received signals and interpreting thetype of inhibit message received by antennae 902.

[0068] Device 900 includes a set of optics 906 for capturing an opticalimage in response to a user input signal. Imaging device 907 is coupledwith optics 906 for converting the received light image of optics 906into two dimensional image data as one or more image data frames,including still images and/or video sequences of a plurality of imageframes. Imaging device 907 drives image memory 908 for processing imagedata frames that in turn selectively drives image data storage device909 for storing captured images. Image processor 910 responds to messagerecogniser 905 to apply data processing to captured image data frames.The data processing that processor 910 performs is in accord with thevarious prior art techniques previously described in connection withFIGS. 6 and 7. Image capture device 900 also includes a set of usercontrols 911 for controlling capture of images via the imaging device907, and for controlling other functions such as storage of images inthe image data store 909, and for monitoring image processing of imagedata. Device 900 also includes an image viewer 912, for example a liquidcrystal display (LCD) or the like, driven by imaging device 907 forviewing captured images. The antenna, receiver, direction finder,message recognizer and image processor constitute an image inhibitormodule 913. The battery or other power supply in casing 901 powerselectronic parts 903-905 and 907-912.

[0069] The inhibit signal transmitted by the inhibitor device 800 can bea visual signal, for example a red coloured visual signal emitted by alight emitting device at a wave length of approximately 633 nm, or agreen light emitted by an LED at a wave length of approximately 510 nm,or may comprise an infrared signal or a microwave or RF frequencysignal.

[0070] In various alternative embodiments, signal detector 901 andreceiver 903 can be an optical detector, such as a photo diode, fordetecting visual or infrared signals; an ultrasonic detector fordetecting ultrasonic signals, or an antenna for detecting radiofrequency signals.

Registration of Inhibitor Devices

[0071] In a further modification of the image capture system describedherein, individual inhibitor devices are registered with individualimage capture devices, so as to override the normal inhibitor functionof the inhibitor device with respect to those particular registeredimage capture devices. This function is useful in situations whereinhibitor devices are worn by members of a family group, and one or moreother members of the family group are carrying an image capture device.Persons within the family group may wish to have their image captured bytheir own family member, but want to prohibit capture of their images byother unknown third parties in a public place.

[0072]FIG. 10 is a schematic drawing of an image capture system, inwhich a plurality of inhibitor devices are pre-registered with one ormore image capture devices, and in which the image capture device canignore an inhibitor message emanating from a pre-registered inhibitordevice. An image capture device 1000 receives first and second inhibitormessage 1001, 1002 from first and second inhibitor devices 1003, 1004respectively within a field of view of the image capture device. Firstinhibitor device 1003 sends an inhibitor message 1001 including a codewhich the image capture device 1000 recognises as denoting a knownpre-registered inhibitor device. On the other hand, second inhibitordevice 1004 sends a signal which is not recognised by image capturedevice 1000.

[0073]FIG. 11 is a flow chart of processes carried out by image capturedevice 1000 upon receiving an inhibit message, for checking whether theinhibit message relates to a pre-registered inhibitor device. Duringstep 1100, the image capture device 1000 receives an input message.Device 1000 then, during step 1701, reads the message, and checks for anidentification code. If device 1000 recognises the identification codeas one which is pre-registered with the image capture device (step1102), the image capture device advances to steps 1103 and ignores theinhibit message, and therefore takes no action to process parts of acaptured image identified by the existence of the inhibit message. Inother words, device 1000 does not modify any part of the image. However,if during step 1102, device 1102 does not recognize the identificationcode as one which is pre-registered with the image captured device,operation advances to step 1104, during which the image capture device1000 restricts a portion of the image corresponding to the inhibitmessage in step 1104.

[0074] Consequently, for an image in a field of view where a pluralityof inhibitor devices are present, some of which are recognised by theimage capture device 1000 and some of which are not, the image capturedevice modifies portions of the image corresponding to inhibitordevices, which are not recognised, and leaves un-modified portions ofthe image corresponding to inhibitor devices having recognised code.

[0075] Widespread usage of inhibitor devices can affect security camerasused in surveillance systems. In an environment such as a buildingsociety, bank, shop, gasoline filling station or the like public place,which are susceptible to criminal activity, criminals wearing inhibitordevices might inhibit a security camera to obscure details of thewearers' faces. Therefore, an embodiment includes a facility wherein aninhibit signal received by an image capture device can be overridden sothat faces of wearers can be viewed. There are two main options foroverriding the inhibit signal, that is (a) without the wearer'spermission; and (b) with the wearer's permission.

[0076] A system wherein the inhibit signal can be overridden without thewearer's permission can be provided as a function built into the imagecapture device itself. However, building in such a function seriouslycompromises the privacy of wearers of inhibitor devices. In a moresophisticated embodiment, an operator of an image capture device canoverride an inhibit signal, only with permission of a trusted thirdparty. In such a system, an operator of an image capture system sends animage to a trusted third party, having the modified image portionscorresponding to a person's face, along with a request to reverse theobliteration of a specific person's facial features.

[0077]FIG. 12 is a flow diagram of a signal processing channel within animage capture device for storing a captured scene image in such a waythat the image can only be viewed, stored or printed with personaldetails obscured of persons wearing inhibitor devices, but with acapability of obtaining a clear image of those persons with externalauthorisation from a third party.

[0078] In step 1200, image capture device 1000 captures an image scenesimultaneously with receiving an inhibit signal during step 1201. Duringstep 1202, device 1000 identifies a portion of the scene image which isrestricted by the inhibit signal. During step 1203 device 1000 encodesthe identified portion of the image and then during step 1204 stores theimage in an encoded format; encoding during step 1204 can includeencryption, and protection with an encoding key. Therefore, if anencryption key is used device 1000 can only store inhibited portions ofthe image in an encrypted format under protection of the encryption key.

[0079] During step 1205, device 1000 processes the scene image so thatinhibited portions of the scene are obscured or obliterated. Theprocessed scene image, having portions of the image obliterated orobscured is then stored during step 1206, and/or made available forviewing or printing during step 1207.

[0080]FIG. 13 includes a communication network 1300 between an imagecapture device 1303 (in the form of a digital video camera) and atrusted third party computer 1301. Communication link 1304 is, forexample, the Internet, for ascending an encoded image portion to atrusted computer authority 1301, for decoding, so that images of personscan be recovered from the encoded stored image portions under control oftrusted authority 1301. When an operator of the image capture device1303 wishes to obtain a clear image of a particular person who hasinhibited capture of the image of the particular device using aninhibitor device, the user can only do so provided the trusted authority1301 agrees to authorise production of a clear image portion free of theparticular person. The operator of the image capture device 1303 cannotbypass the trusted authority 1301, since the stored image portions areencrypted, and can only be decrypted with a key available to an operatorof the trusted authority.

[0081] Several further variations on the embodiments described hereincan be incorporated as follows.

[0082]FIG. 14 is a schematic illustration of a system includinginhibitor device 1600 and a digital video camera that comprises imagecapture device 1601, and a remote trusted third party computer 1602. Animage of a host wearer of inhibitor device 1600 is coupled to either animage inhibitor module (the same as module 913) within the image capturedevice 1601, and/or to a trusted third party computer 1602. The image iscoupled to computer 1602 via a cellular telephone camera (not shown)that communicates with computer 1601 via a communicator network 1603that can include a cellular phone network and the Internet. The image ofthe host wearer of the inhibitor device 1600 can be sent to computer1602 either as a clear un-encoded image, or it can be sent as an encodedimage, in order to prevent misappropriation of the image when it isbeing coupled between the person wearing inhibitor device 1600 and theimage capture device 1601 or between the person wearing inhibitor device1600 and the trusted third party computer 1602.

[0083] Image inhibitor device 1600 also transmits to an inhibit signalthat is coupled to image capture device 1601 and/or computer 1602.Transmission of the inhibit signal from device 1600 to computer 1602 isvia network 1603.

[0084] Operation of the image capture system of FIG. 14 is as follows.Image capture device 1601 captures an image of a scene in the opticalfield of view of the image capture device 1601. Within that scene, theremay be one or more inhibitor devices 1600. The inhibitor devices 1600announce their presence within the field of view to the image capturedevice 1601, by transmitting a recognition signal, which can be theinhibitor message as described previously with respect to the embodimentof FIG. 1. However, in addition to that message, the inhibitor device1600 coupled to the image capture device 1601 an image of the hostwearer. The image capture device 1601 matches that received image, witha portion of the image captured by the image capture device 1601, whichcorresponds to a host wearer of the inhibitor device 1600. Devices 1601matches the image of the wearer of inhibitor device 1600 with a portionof the image scene captured by the image capture device 1601 by patternmatching or pattern recognition algorithms which match the host wearer'sfacial image with positions of the captured image scene to detect amatch of profiles.

[0085] The image of the wearer of the inhibitor device 1600 sends to theimage capture device 1601 may comprise several views of the face of thewearer of device 1600, so that the face can be recognised from a varietyof different view angles.

[0086] In a further mode of operation of the embodiment of FIG. 14, theimage(s) of the host wearer's face are sent to a trusted third partycomputer 1602 operated by an independent authority having responsibilityfor decoding portions of an image. The trusted third party computer 1602uses the host wearer's image to recognize portions of a scene imagewhich have been sent to the computer by image capture device 1601, todecode that part of the image as described previously with respect ofthe embodiment of FIG. 13. In this mode of operation, which hasapplication for obtaining decoding of images taken by a security camera,the operator of the image capture device 1601 must obtain authorizationto decode a portion of the image. The trusted third party computer 1602uses the inhibit signal and the image of the wearer of device 1600, asreceived from network 1603, to decode an obliterated or modified portionof the scene image corresponding to the wearer's face, so that theoperator of the image capture device 1601 can obtain from the trustedthird party, a clear image of the host wearer's face.

Activation of the Image Inhibitor Module

[0087] In a further variation of the embodiments described herein,activation of an image inhibitor device depends upon either the distancebetween an image capture device and an inhibitor device, or an effectiveresolution of an image which the image capture device can capture.

[0088] In the first case, an inhibitor device and/or an image capturedevice are provided with known distance measuring devices, for example adiode laser based measuring system as known in the art. The imagecapture device measures the distance between itself and the inhibitordevice within an optical field of view of the image capture device. Inresponse to the distance measurement, the image inhibitor module of theimage capture device is activated or de-activated. For inhibitor deviceswhich are beyond a pre-specified range the image inhibitor module of theimage capture device is deactivated, allowing the image capture deviceto store, print or display a scene image including an un-modified imageof a host wearer's face. If the pre-specified distance is set correctly,the person will be so far in the distance, that the person will appearonly as a small feature in the captured image, and it is difficult orimpossible for persons examining that image to recognise the wearer ofthe inhibitor device due to the relatively small size of the image ofthe person as a proportion of the entire scene image.

[0089] In the second case, the image inhibitor module of the imagesensor does not modify any image portions where facial features are notrecognised due to the low resolution of the facial features. Forexample, this may be because the wearer of an inhibitor device is so faraway from the image capture device within an optical field of view ofthat device or the field of view is so dark that the facial features ofthe viewer cannot be captured with a significantly high resolution suchas to enable a person to recognise the wearer of the inhibitor device.

[0090] In a further variation, the inhibitor device worn by a person isin the same casing as an image capture device, to provide an imagecapture device performing the dual role of enabling a person to captureimages of a scene, while the same time providing a degree of privacy tothat person from having their image captured by other image capturedevices. For example, the inhibitor device, and an image capture devicehaving an image inhibitor module, can be incorporated in a single handheld device, for example a mobile phone, or still image camera, or handheld video camera device.

[0091] In a further variation, within the image capture system,individual security groups or levels of security can be implicitly orexplicitly used to ensure that if a person carries an inhibitor device,it will still be possible for an authorised person, for example a familymember, to be able to capture an image of the wearer of the inhibitordevice.

[0092] By combining an inhibit message or inhibit signal with patternrecognition of facial features, that is, by comparing an image sent bythe inhibitor device with portions of a scene image, a portion of ascene image relating to a wearer's face can be more accurately adjustedand finally located, and modified to obscure the facial details of thatperson.

[0093] Specific embodiments disclosed herein provide that a person whodoes not want his image to be captured can carry a portable device tocommunicate with one or more image capture devices, such as a camera,which that person may encounter, to inhibit those image capture devicesfrom using images of the person. The image capture system isde-centralised, and need not rely on a centralised database of images ofthe person's face.

1. A method of modifying a captured image of a scene, said methodcomprising: detecting an inhibit signal emanating from an inhibitordevice carried by an object within said image; in response to saidinhibit signal, identifying a portion of said image corresponding tosaid object; and modifying said image of said scene to render the objectunidentifiable from the modified image.
 2. The method as claimed inclaim 1, wherein identifying a portion of said image corresponding tosaid object comprises: locating a source of said inhibit signal withinsaid image of said scene.
 3. The method as claimed in claim 1,comprising: identifying a region of said image of said scene in whichsaid image portion corresponding to said object is positioned, byidentifying a position of said captured image corresponding to a sourceof said inhibit signal.
 4. The method as claimed in claim 1, whereinidentifying a portion of said image corresponding to said objectcomprises: searching said image of said scene for a relatively higherintensity light spot corresponding to said inhibit signal.
 5. The methodas claimed in claim 1, wherein said object is a person and said step ofidentifying a portion of said image corresponding to said personcomprises: detecting skin tone detail within said image of said scene.6. The method as claimed in claim 1, wherein identifying a portion ofsaid image corresponding to said object comprises: recognizing anoutline of said object within said image of said scene.
 7. The method asclaimed in claim 1, wherein said object is a person and identifying aportion of said image corresponding to said person comprises: applying afacial recognition algorithm to said image of said scene, in order torecognize a portion or said image corresponding to a face of saidperson.
 8. The method as claimed in claim 1, wherein identifying aportion of said image corresponding to said object comprises: applyingan object recognition algorithm to said image of said scene, in order torecognize a portion or said image corresponding to said object.
 9. Themethod as claimed in claim 1, wherein modifying said image of said sceneso as to obscure said image portion of said object comprises: decreasingthe resolution to said image portion of said object.
 10. The method asclaimed in claim 1, wherein modifying said image of said scene so as toobscure said image portion of said object comprises: overlaying agraphic image on said image portion.
 11. The method as claimed in claim1, wherein modifying said image of said scene to obscure said imageportion of said object comprises: defocusing said image portion of saidobject.
 12. The method as claimed in claim 1, wherein modifying saidimage of said scene so as to obscure said image portions said objectcomprises: darkening said image portion of said object.
 13. A portableinhibitor device for use by a user, comprising a transmitter of aninhibitor message for inhibiting an image capture device from processinga portion of said image corresponding to the user of said user portableinhibitor device.
 14. The user portable device as claimed in claim 13,wherein said inhibitor device is arranged to transmit said inhibitormessage directionally.
 15. The user portable device as claimed in claim13, wherein said inhibitor device is arranged to transmit said inhibitorsignal omni-directionally.
 16. The user portable device as claimed inclaim 13, wherein said transmitter is arranged to transmit the inhibitormessage comprises an infrared signal.
 17. The user portable device asclaimed in claim 13, wherein said transmitter is arranged to transmitthe inhibitor message as a visual signal;
 18. The user portable deviceas claimed in claim 13, wherein said transmitter is arranged to transmitthe inhibitor message as a radio frequency signal.
 19. An image modifierarranged to be responsive to an inhibit signal adapted to be transmittedfrom an object, the modifier comprising: a receiver for the inhibitsignal, a processor arrangement connected to be responsive to thereceiver for performing the following questions in response to thereceiver receiving the inhibit signal: (a) identifying an image of atleast one object within an image of a scene; (b) determining whether theimage of said at least one object should be excluded from the image ofthe scene; and (c) modifying said scene image to obscure said image ofsaid at least one object.
 20. A method for restricting usage of an imageof an object, said method comprising: transmitting an inhibitor signalfrom a position close to the object; receiving said inhibitor signal atan image capture device within the optical field of view of said object;and applying a restriction on a captured image of said object, ascaptured by said image capture device, in response to receipt of saidinhibitor signal.
 21. An image capture device arranged to be responsiveto an inhibit signal adapted to be transmitted from an object, themodifier comprising: an imaging system for capturing image data; animage inhibitor module for receiving the inhibitor signal; an imageprocessor activated in response to the image inhibitor module receivingthe inhibit signal for (a) selecting portions of said captured imagerelating to inhibited matter, and (b) modifying said inhibited matterportions of said image, so as to obscure said inhibited matter.
 22. Amethod of processing a captured image of a scene, said methodcomprising: receiving an inhibit signal originating proximate to thescene, the signal being for inhibiting processing of a portion of saidscene image; in response to receipt of the inhibit signal; (a)identifying a portion of said scene image to which said inhibit messagerelates; and (b) inhibiting viewing of said identified image portion byprocessing said identified portion of said scene image.
 23. The methodas claimed in claim 22, wherein said inhibit signal is received from aposition within a field of view of said scene image.
 24. The method asclaimed in claim 22, wherein said inhibit message comprises a region ofrelatively high intensity lights within said scene image.
 25. The methodas claimed in claim 22, further comprising: searching for an inhibitmessage within said scene image; searching for a portion of inhibitedmatter within said scene image, adjacent said inhibit message; andobscuring said inhibited matter from view by processing said region ofinhibited matter in said scene image.
 26. An image capture systemcomprising: an inhibitor device arranged to be carried by an object forinhibiting processing of an image of said wearer; at least one imagecapture device, said image capture device including an image inhibitorcomponent for inhibiting processing of portions of an image captured bysaid image capture device; and an encoder for encoding a portion of saidimage, said image portion corresponding to an image of said object. 27.The image capture system as claimed in claim 26, further comprising atrusted third party computer device, said trusted third party computerbeing arranged for: receiving an encoded image portion; and decodingsaid image portion.
 28. The image capture system as claimed in claim 26,further comprising a trusted third party computer device, said trustedthird party computer being arranged for: receiving an encoded imageportion; and decoding said image portion; said image capture devicebeing arranged to send said encoded image portion to said trusted thirdparty computer; said trusted third party computer being arranged todecode said encoded image portion to produce a clear image of a personand to send said decoded clear image to said image capture device. 29.An image capture system comprising: an inhibitor device adapted to bemounted on an object for inhibiting processing of image datacorresponding to said host wearer; and an image capture devicecomprising an image inhibitor component for restricting processing ofimage data corresponding to one or more objects within a captured sceneimage; said inhibitor device being arranged for sending at least oneimage of a host wearer of said inhibitor device to said image capturedevice, such that said image capture device can use said received imagefor recognizing an image portion corresponding to said object, withinsaid captured scene image.
 30. An image capture system comprising: aninhibitor device adapted to be carried by an object, for inhibitingprocessing of image data corresponding to said host wearer; and a thirdparty computer entity comprising an image inhibitor component forrestricting processing of image data corresponding to one or moreobjects within a captured image scene; said inhibitor device beingarranged for sending at least one image of a host wearer of saidinhibitor device, to said third party computer entity, such that saidthird party computer entity can use said received image for recognizingan image portion corresponding to said object, within said capturedscene image.
 31. An image capture device comprising: an optics systemfor forming an image on a detector; and an image inhibitor operable forreceiving externally of said image capture device, an inhibit signal forinhibiting a portion of said captured image, and inhibiting viewing ofthe portion of the image accordingly.
 32. The image capture device asclaimed in claim 31, further comprising: a portable inhibitor device,said inhibitor device being arranged for sending an inhibit message forinhibiting viewing of a portion of said captured image relating to ahost wearer of said image capture device.
 33. A method of modifying acaptured image of a scene, said method comprising: detecting aninhibitor signal generated from a position within said scene image;responding to said inhibitor signal by identifying an image portion ofat least one object within said scene image; determining that said imageportion of said object should be excluded from said scene image; andmodifying said scene image so as to exclude a detail of said imageportion of said at least one object within said captured image of saidscene.
 34. The method as claimed in claim 33, wherein determiningwhether said image of said object should be included or excludedcomprise: receiving an inhibit message for inhibiting a portion of saidimage.
 35. The method as claimed in claim 33, wherein identifying animage of at least one object comprises: locating a source of aninhibitor signal within said scene image; and recognizing a portion ofsaid object by applying a recognition algorithm for a portion of saidobject to said scene image.
 36. The method as claimed in claim 33,comprising: receiving an inhibit message for inhibiting said image ofsaid at least one object; and identifying a region of said scene imagein which said image of said at least one object is positioned.
 37. Themethod as claimed in claim 33, wherein identifying an image of at leastone object within said scene image comprises: searching said scene imagefor a relatively high intensity light spot corresponding to a said atleast one object.
 38. The method as claimed in claim 33, whereinmodifying said scene image so as to obscure said image of said at leastone object comprises: decreasing the resolution to said image of said atleast one object.
 39. The method as claimed in claim 33, whereinidentifying an image of at least one object comprises: recognizing anoutline of said image of said at least one object within said sceneimage.